基于适配体与聚多巴胺纳米粒的荧光内滤效应研究

Fluorescence Internal Filtration Effect Based on Aptamer and Polydopamine Nanoparticles

在弱碱性条件下,采用一锅法通过多巴胺氧化自聚制备聚多巴胺纳米颗粒,利用红外光谱、透射电镜、粒径电位仪对其进行表征,成功制备出光滑、圆整、均一、稳定性好,平均粒径270 nm的聚多巴胺纳米粒,并利用荧光分光光度法和紫外吸收法研究适配体和聚多巴胺纳米粒之间的内滤效应和作用机制。研究表明,聚多巴胺纳米粒的紫外吸收和适配体的激发光谱之间有很大程度的重叠,荧光强度随溶液浓度增大下降现象明显,且二者之间形成了动态猝灭。

Under weak alkaline conditions,polydopamine nanoparticles were prepared by one-pot oxidation and self-polymerization of dopamine,and characterized by infrared spectroscopy,transmission electron microscopy and particle size analyzer.Polydopamine nanoparticles with smooth,round,uniform,good stability and average particle size of 270 nm were successfully prepared.The internal filtering effect and mechanism between aptamer and polydopamine nanoparticles were studied by fluorescence spectrophotometry and ultraviolet absorption method.Studiesshowed that there was a large degree of overlap betweenUV absorption of polydopamine nanoparticles and the excitation spectra of aptamers.The fluorescence intensity decreased significantly with the increase of solution concentration,and a dynamic quenching was formed between them.